Wilhelm Johannsen
Wilhelm Johannsen is the name of the following people:
- Wilhelm Johannsen (architect) (1857–1917), Danish-Russian architect.
- Wilhelm Johannsen (botanist) (1857–1927), Danish botanist and geneticist
- Wilhelm Johannsen (artist) (1897–1938), German painter, graphic artist and art teacher
See also:
- Willi Johannsen (1904–1976), German politician (SSW)